2D - Gene Expression Flashcards
gene expression
the process of
reading the information stored within a gene to create a functional
product, typically a protein
pre mRNA
the immediate
product of transcription of a DNA
sequence. Requires modifications
before it can undergo translation
steps of transcription
RNA polymerase binds - pR- initiate transcription.
DNA unwinds exposing the template strand.
RNA polymerase reads the DNA template strand (3’ to 5’) and catalyzes transcription by joining complementary RNA nucleotides.
Pre-mRNA is synthesized, complementary to the template strand.
a-u instead of a-t
terminated when termination sequence recognised by rna p
what occurs during rna processing and what is another name for it
post transcriptional modifications
- addition of 5’ methyl cap, 3’ poly-A tail
-removal of introns and splicing of exons
purpose of Addition of a 5’ methyl-G cap and a 3’ poly-A tail
serve to stabilise the mRNA molecule, preventing it
from degrading and allowing it to bind to ribosomes during translation.
alternative splicing
the process
where different exons may be spliced, resulting in a single gene
producing multiple different
mRNA strands
translation
reading and converting the information carried in the mRNA molecule into a polypeptide chain.
translation overview
mRNA molecule binds
to the ribosome
* tRNA anticodons complementary to
mRNA codons deliver corresponding
amino acids to the ribosome
* Adjacent amino acids are joined with
peptide bonds via a condensation
reaction to form a polypeptide
* Translation ends when a STOP codon
is recognised